Vehicle control apparatus



Nov. 1, 1938. 5, FOLBERTH AL 2,135,071

VEHICLE CONTROL APPARATUS CttornegS 3nventors v 7 Nov, 1,1938. F; ..G.FOLBERTH 5r AL 2,135,071

VEHICLE CONTROL APPARATUS Filed Dec. 1, 1955 3 Sheets-Sheet 2f vattorneys Nov. 1, 193a. F;.FL BERTH Em 2,135 071 VEHICLE CONTROL-APPARATUS Filed Dec. '1, 193a s Sheets-Sheet s V I 3nventors 5. a &FEEDER/5A G-FOZBEPTH g mum/v MFOABE/PTH I attorneys Patented Nov. 1',1938 1 i a I 2,135,071 1 I UNITEDSTATES PATENT orrics VEHICLE CONTROLAPPARATU S Frederick G. Folberth and William M. Folberth, Cleveland,Ohio Application December 1, 1933, Serial No. 700,470

9 Claims (Cl. 192-.01)

This invention relates to control apparatus for mechanism by which thevehicle brakes will be automotive vehicles and more particularly toapapplied in case the operator either accidentally paratus forfacilitating the control of an automoor intentionally removes his footfrom the conbile and reducing the effort and skill required trol pedal;the provision of fluid pressure actuto be exercised by the operator ofthe vehicle. ated means for operating the clutch and brakes 5 In ourco-pending United States patent appliof an automotive vehicle whichmeans is adaptcation, Serial No. 522,182, filed March 12, 1931, ed to becontrolled by movement of the usual we have described and claimed afluid pressure foot operated accelerator pedal and which is paractuatedcontrol apparatus whereby the clutch ticularly adapted to economicalmanufacture and 10 of an automotive vehicle is automatically disenwhichmay be readily installed on standard types 10 gaged when the operatorcloses the throttle of of automobiles at minimum expense. the vehicleengine. It has also frequently been The abovegand other objects of ourinvention proposed and numerous devices have been de-' will appear fromthe following description of one vised for actuating the brakes of anautomotive embodiment thereof, reference being had to the vehicle byfluid pressure. The vacuum created accompanying drawings, in which- 15in the intake manifold of the vehicle engine Figure 1 is a'fragmentaryview of the front during operation is aconvenient source of end of anautomobile, partly in section, and lower than atmospheric pressure whichmay be illustrating our improved control mechanism incontrolled tooperate automatic clutch mechastalled, the parts being in the positionsthey asnisms of the type described in our above noted sume when thevehicle engine is running and the 20 copending application and fluidpressure actudriver completely removes his foot from the conated brakemechanisms. trol lever.

In our present invention we have provided a Figure 2 is an enlargedfragmentary view of control system for automotive vehicles whereby theapparatus shown in Figure 1 but illustrata single pedal is adapted tocontrol the operaing the parts in the positions they assume when 25 tionof the vehicle engine throttle, the clutch the vehicle operator hasdepressed the operatengaging and disengaging movements, and the ingpedal suiliciently to permit the qrakes to be application and release ofthe vehicle brakes. released but before he has moved the pedal sufll-With our improved arrangement the operator of ciently to cause theclutch tobe engaged and the vehicle uses only one foot to control all ofthethrottle to be opened to start the vehicle. 30 these operations anddoes not need to remove Figure 3 is an enlarged side elevation of ourthis-foot from the single control pedal. Itwill improved unitary valvemechanism for controlbe understood by all who are familiar with preslingthe operation of the vehicle brakes and cut day vehicles that thisarrangement consticlutch.

3.3 tutes a great improvement over the usual con- Figure i ls a verticalcross section through the trol arrangement for automobiles in whichinvalve shown in Figure 3, the valve closure memdependent pedals areprovided for the operation her being in'its top position in which boththe of the vehicle clutch, the vehicle brakes and the brake and clutchoperating cylinders are conthrottle or accelerator. With our singlepedal nected to the atmosphere.

control system the operation of an automotive Figure 5 is a crosssectional view of the valve 40 vehicle is greatly simplified and theeffort and shown in Figure 3 taken on line 55 of Figure 4. skillrequired is greatly reduced. Figure 6 is a cross sectional view of thevalve It is among the objects of our invention to shown in Figure 3taken on line 6 6 of Figure 4. provide an improved control system forautomo- Figure 7 is a cross sectional view of the valve tive vehicles inwhich thestarting, stopping and shown in Figure 3 taken on line -'l| ofFigure 4. 45 the acceleration and deceleration of thevehicles Figure 8-is a cross sectional view generally are controlled'by a single footoperated-"lever or similar to- Figure 4 butillustrating the valve pedal;the provision, in control apparatus for 1111- closure member in positionto connect the clutch tomotive 'vehicles, of a fiuid pressure actuatedoperating cylinder to the source of operating 1 clutch and a fluidpressure actuated brake, topressure (the vehicle intake manifold) butwith 5 gether with a single unitary valve means adapted the brakeoperating cylinder still connected :to to control the action of both thebrake and the the atmosphere. clutch and to properly time the operationof these Figure 9 is a view similar to Figure 4 but illusunits'so thatthe brakecannot be applied when trating the valve closure member in itslowest the clutch is engaged; the provision or a control. position in.which both the brake operating cylinder and the clutchoperating-cylinder are shut off from the atmosphere and connected to theintake manifold suction and the top end of the piston closure member issubjected to the brake cylinder pressure to give the desired brakingaction.

Figure 10 is generally similar to Figure 2 but illustrates a modifiedcontrol lever arrangement.

Figure l. illustrates our control apparatus installed upo .1 anautomotive vehicle equipped with the usual clutch, brake and throttleoperating pedals. It will appear as this decription progresses that withour apparatus the usual clutch and brake operating pedals -might beentirely dispensed with but, as we are illustrating the application ofour invention to a standard type of automobile, they will be included inthis description. The vehicle brake operating lever I extends throughthe floor board 2 and is provided with a foot pedal in the usual manner.The lower end of the pedal is pivoted as at 3 and operates the brakerods 4 and 5 which are connected through any suitable linkage to operatethe brakes 6 on the vehicle wheels. The clutch operating lever I alsoextends through the floor board 2 and is provided with the usual footpedal and may also be conveniently pivoted at 3. The lower end of thepedal 1 is connected to cause the clutch 8 to be disengaged when thelever I is moved downwardly. The usual clutch engaging springs (notshown) cause the clutch to be engaged when the pressure on the lever Iis released and the usual brake retracting springs (not shown) willcause the lever I to be returned to its released position when theoperating force on the lever I is removed.

To operate the vehicle brakes we prefer to provide a cylinder 9 in whichis disposed a piston I0 having a piston rod II extending out through theend of the cylinder 9 and connected to the lever I by a cable I2. Thecylinder 9 is preferably pivotally supported at its lower end on abracket I3 which may be secured to the crank case of, the vehicle engineor other suitable and convenient support.

The clutch operating cylinder I4 is pivotally supported on a similarbracket I5 and carries a piston I6 having a piston rod which isconnected to the clutch operating lever I by the cable I8. We prefer toprovide the clutch operating cylinder I4 with means for permitting rapidinitial movement of the piston I6 in clutch engaging direction and thenrelatively slow and gradual movement of the piston I6 during the actualengagement of the vehicle clutch. This mode of operation and means foraccomplishing same are clearly described in our above noted co-pendingapplication, but as details thereof do not form a part of the presentinvention they will not be more fully described here.

Our improved control valve, generally indicated' at V, is adapted tocontrol the fiuid connections to both the brake cylinder 9 and theclutch cylinder I4. This valve V is supported by an angle pipe I9 whichalso provides the connection between the valve V and the interior of thevehicle engine intake manifold 20. A fluid pressure conducting conduit2! extends from the valve V to the brake cylinder 9 and another conduit22 extends from the valve V to the clutch cylinder I4. The singlecontrol pedal 23, as illustrated, is of the type usually used for thefoot throttle control of an automobile. This pedal 23 is pivotallysupported on a bracket 24 which is mounted on the dash board 2 Of t evehicle. A throttle operating lever 25 is also pivotally supported bythe bracket 24 and the levers 23 and 25 are independently movablealthough mounted on the same supporting pin 24'. The lever 25 isprovided with a lug 25 and the lever 23 is provided with a lug 23' whichlugs are so disposed that they will engage and cause the lever 25 tomove with the lever 23 during a part of its movement as will be laterdescribed. A rod 26 connects the lower end of the lever 25 to thethrottle arm 21 which is mounted on the carburetor 28 and operates thebutterfly type of throttle valve 29. vfIhe upper end 23" of the lever 23extends beyond the pivot point 24 and is provided with an aperturethrough which extends the valve loading spring 30. An adjustable collar3| is clamped to the spring 39 by the screw 3| and forms an abutmentagainst which the end 23" of the lever 23 may strike to exert a downwardpull on the spring 30. The spring 32 is secured at its lower end to asuitable bracket 33 which may be mounted on the engine block and at itsupper'end to a pin or bracket 34 which is carried by the end 23" of thecontrol lever 23. This spring 32 is heavier than the spring 30 and isnormally maintained in extended position under tension and thereforeexerts a downward pull on the end 23" of the control lever 23. A spring34 connects the lower end of lever 25 to a bracket 35 on the floor board2 and exerts a force tending to move lever 25 toward the floor board andclose the throttle valve 29. The movement of lever 25 and valve 29 inclosing direction is limited by the adjustable stop screw 35.

Before describing the operation of our control apparatus it will be wellto describe our improved unitary brake and clutch controlling valve V.This valve is illustrated in detail in Figures 3 to 9 inclusive andreference is made to these figures of the drawings in the followingdescription.

Our valve comprises a generally cylindrical body or housing 40 having abore 4| extending therethrough. The upper end of the bore is closed by acover plate or cap 42 which is secured to the housing 4|] by screws 43.The joint between the cap 42 and the housing is made fluid pressuretight by a suitable packing washer 44.

A bottom cap member 45 is secured to the lower end of the housing 40 byscrews 46 and is provided with a central aperture through which thevalve closure member operating rod 41 extends. The cap 45 is alsoprovided with vent holes 48 which connect the lower end of the bore 4|to the atmosphere. A stop screw 49 extends through the top end cap 42and acts to limit the upward movement of the piston closure member C,.aswill be later described.

This closure member C comprises three spaced piston-like closureportions adapted to havea sliding fit within the bore 4| and connectedtogether by portions of reduced diameter. The

upper closure portion 50 is adapted to control of one piece and theoperating rod 41 extends downwardly from the closure portion 52 and isprovided with a hole in its lower end to which is attached the spring30. A compression spring 58 is disposed between the inner surface ofthe.

end cap 45 and the underside of the closure portion 52.- This spring isnormally under compression and tends to maintain the closure member C inits uppermost position against the stop screw 49, as shown in Figure 4.

The housing 40 is provided with a plurality of ports which extendthrough its wall and which cooperate with the closure member C to obtainthe desired fluid pressure connections. The top port 51 extends throughthe side wall of the housing 40 and is adapted to connect the interiorbore 4| with the atmosphere. The port 51 is an elongated slot (best-seenin Figure 5) which extends for substantially 180 of the circumference ofthe bore 4|. Below the port 51 and on the opposite side of the housing40 is another port 58 which connects the bore 4| with the tube 59 towhich the conduit 2|, which leads to the brake cylinder 9, is attached.The atmospheric port 60 for the clutch cylinder extends through the wallof the housing 40 on the .same side and below the port 58 and consistsof an elongated slot similar to the port 51. Below the port 60 is theport 5| which connects the bore 4| with the tube 62 to which the conduit22, leading to the clutch operating cylinder, is attached. Below thebrake cylinder atmospheric port 51 and on the same side of the housing40 are the vacuum ports 63' and 64. These ports extend from the bore 4|to a common chamber 65 (see or seize in the bore 4| is eliminated andthe closure member is freely movable verticaliy at all times andregardless of its position relative to the ports.

The upper end of the bore 4|, above the closure portion of the pistonclosure member C, forms a cylinder and a fluid conducting passageway 68is formed in the wall of the housing! and connects the bore 4|, abovethe closure portion 50, to the port 58. By this connection the samepressure conditions are maintained on the top of the closure member C asobtain within the brake cylinder. This is an important feature insecuring the proper braking action, as will be later explained. It willbe understood that the lengths of the cylindrical closure portions 50,5| and 52 will be correlated with the vertical spacing of the ports51,58, 60, SI, 63 and 64 so that the proper sequence of operations ofthe vehcle brake and clutch will be obtained. As is bes seen in Figures3 and 5 the wall of the housing 40 may be cut away adjacent the ports'51 and s Figure 1 it will be assumed that the vehicle engine isrunning-thereby creating a suction ,or reduced pressure in the intakemanifold 20, and the operator has removed his foot from the "con- .hisfoot to the operating pedal 23.

trol pedal 23. The spring 32, being stronger than the spring 30, hasmoved the upper end 2.3" of the operating lever 23 downwardly againstthe stop 3| thus exerting a pull on the spring 30 which is transmittedto the closure member C through the operating rod 41. This downward pullon the closure member C overcomes the force of the spring 56 and movesthe closure member C into its lowest position, as shown in Figure 9..When in this position the brake cylinder 9 is connected to the intakemanifold suction through the conduit 2|, pipe 59, port 58, bore 4|, port63, chamber 65 and pipes 66 and I9. In like manner the clutch operatingcylinder I4 is connected to the intake manifold 20 through the conduit22, pipe 62, port 6|, bore 4|, port 64, chamber 65 and pipes 66 and I9.Thus, the reduced pressure of the intake manifold will be applied to thelower ends of the cylinders!) and I4 and, as they are 'open to theatmosphere on their upper ends, a pressure difierential will be createdon opposite sides of the pistons II and I"! and they may be moveddownwardly in their respective cylinders. This movement of the pistonswill be transmitted through their connecting rods and the cables l2 andI8 and will move the brake and clutch operating levers I and 1downwardly disengaging the vehicle clutch and applying the vehiclebrakes.

Now when the operator desires to start the vehicle he shifts into theproper gear and applies 1 When the parts are in the positions shown inFigure 2 the operators foot is resting on the pedal 23 and he has movedthe pedal 23 downwardly until the lug 23' strikes the lug 25 of thethrottle operating lever 25. This movement is preferably accomplishedbythe weight of the operators foot without the application ofappreciable muscular effort. At this point an additional resistance tomovement of the pedal 23 is imposed due to the spring 34 and theoperator, by the difference in feel of the movement of the pedal 23,

is advised that he has reached the throttle opers has been lifted thusin part releasing the tension on the spring 30 and permitting the spring56 to lift the closure member C into the position shown in Figure 8. Inthis position the brake operating cylinder 9 is connected to theatmosphere through the conduit 2|, pipe 59, port 58, bore 4| and port41. The clutch cylinder connections, however, have not'changed and theclutch cylinder I4 is still connected to the intake manifold suction, aswas described above in reference to Figure 1. As the lower end of thebrake cylinder 9 is now connected to the atmosphere the pressure on theopposite sides of the piston ID will be equalized and the usual brakeretracting springs will be effective to release the vehicle brakes andmove the operating pedal to its released position. The clutch pedal 2,however, w n still be held in clutch disengaged position due to thesuction which is still applied to the lower end of the clutch cylinderl4.

As the operator pushes the pedal '23 further down the engine throttlewill be opened due-totheengagement of the lugs, 23' and 25 which willcause the lever 25' to move with the lever '23. Such further movement ofthe lever 23 will also cause further release of the tension on thespring 30 and will permit the spring 56 to move the closure member Cupwardly into the position shownin Figure 4. When in this position thebrake cylinder is shut off from the intake manifold by the closureportion 5| and the clutch cylinder is shut oil from the manifold suctionby the closure portion 52. As the closure portions 50 and Si have movedabove the atmospheric ports 51 and 60 the brake and clutch cylinderswill be connected directly to the atmosphere and, 'due to theequalization of pressure on the opposite sides of pistons l0 and 16, theclutch will be moved into engagement by the normal clutch engagingsprings and the brake will still be released. This movement of theclosure member C from the position shown in Figure 8 to that shown inFigure 4 takes place during the first part of the downward movement ofthe lever 23 from the position shown in Figure 2 and thus, when theoperator pushes down on the lever '23, the clutch cylinder [4 willpromptly'be connected to the atmosphere and the clutch will be engagedthus starting the vehicle. As noted above the cylinder I4 is preferablyso arranged that the initial movement of the piston l6 andthe operatinglever 1 in clutch engaging direction will be relatively rapid while thefinal engaging movement will be relatively slow in order to give smoothclutching action. This may be accomplished in a number of ways which arenot described here because they do not form a part of the presentinvention.

When the operator releases the pressure of his foot upon the pedal 23the reverse of the above described action will take place. First thevehicle engine will bethrottled down, next the valve closure member Cwill be moved from the position of Figure 4 into that of Figure 8 andthe clutch cylinder will be connected to the intake manifold suctionthus disengaging the clutch. When the operator further releases thepressure on the lever 23 the tension on the spring 30 will be increaseddue to the action of the spring 32 and this will move the closure memberC toward the position shown in Figure 9. As noted above, when in thisposition the lower end of the brake cylinder is connected to the intakemanifold suction and shut off from the atmosphere. It will also be notedthat the intake manifold suction is now applied to the upper end-of theclosure member C through the passage 68. When the suction within thebore 4! above the closure member C reaches a point where it willovercome the tension of the spring 30 the closure member- C will bemoved upwardly, due to the action of atmospheric pressure on theunderside of the closure portion 52, until the port 51 is opened and theport 63 is closed. This will permit air under atmospheric pressure toenter the bore 4| through the port 51 and will reduce the vacuum withinthe brake cylinder and also on top of the closure member C. When thisoccurs the tension on the spring 30 will again be great enough to movethe'closure member C downwardly until the atmospheric connectionsthrough the port 51 is closed ofi and the vacuum connection through theport 63 again completed. Thus, it will be seen that by the by-passpassage 68 and the piston action of the closure member C a self lappingtype of brake control valve is obtained and the degree of application ofthe vehicle brakes may be varied in accordance with the degree oftension applied to the spring '30. Thus, the operator, by propermanipulation of the operating lever 23 between the position of thislever shown in Figure 1 and its position as shown in Figure vehiclebrakes to secure and maintain any desired degree of braking force.

Figure 10 illustrates a modified arrangement of levers for operating thethrottle 29 and the brake and clutch control valve V. The lever or pedal15 is the usual foot throttle pedal and is pivotally supported at 16.The downwardly extending portion H of the lever 15 is connected to thethrottle operating lever 21 by the rod 18. A spring 19 normallymaintains the throttle operating lever 21 against the adjustable stopscrew 36 thus holding the throttle valve 29 in idling position. Anauxiliary lever is conveniently pivoted at 16, independent of the lever15 however, and has an extension 80 which-engages the operating spring30 of the valve V in the same manner as illustrated in Figure 2. Thelever 80 is provided with a lug portion 8| through which the adjustingscrew 82 extends. The lower end of the screw 82 is adapted'toengage thelever 15 at 83 and the end of the lever 80 is provided with a pad 84,preferably of sheepskin, felt or other soft material, which will preventscratching the vehicle drivers shoe. This pad is preferably disposedsubstantially above the inner end of the throttle operating lever 15 andis normally spaced from the end of lever 75 a distance just slightlygreater than the thickness of the operators foot.

- When the parts are in the positions shown in Figure 10 it may beassumed that the operator has just inserted his foot between the pad 84and the pedal 15 but has not exerted upward or downward pressure onthese levers. When in this po sition the throttle 29 is closed, thevalve V has been moved by the spring 19, through action of the lever 15upon the adjustable screw 82 to move the end 80' 0f lever 80 downwardly,just enough to cause disengagement of the vehicle clutch but not enoughto cause application of the vehicle brakes. If the operator wishes tostart the ve hicle he depresses the lever 15 whereupon the valve V willbe moved by means of spring 56 into position to permit the clutch to beengaged and the-throttle will be opened tospeed up vthe'engine. If theoperator now wishes to apply the vehicle brakeshe rocks his footupwardly about his heel thus removing the pressure from the lever 15 andpermitting the spring 19 to return,

to its normal position and lifting the end of the lever 80 with the topof his foot. This upward movement of the pad 84 will cause the end 88 oflever 80 to move downwardly exerting a tension on the spring 30 whichwill cause the vehicle brakes to be applied to the desired'degree, ashas been previously explained in connection with the operation'ofthevalve V. With this arrangement the brakes of the vehicle will notnormally be held in applied position when the vehicle .engineis runningand the operator has completely removed his foot from operating positionbetween the levers 15 and 80 although the clutch will be maintained indisengaged position.

From the above description it will be seen that we have provided acontrol mechanism for automotive vehicles by which automatic control ofthe vehicle clutch,-smooth and flexible fluid pressure control of thevehicle brakes to obtain any desired degree of braking action, and theusual control of the vehicle throttle may be obtained by simple movementof only one foot of the operator. Our apparatus, and particularly ourimproved control valve, is extremely simple, compact and trouble proof,and although we have described the illustrated embodiment of ourinvention in considerable detail, it will be understood by those skilledin the art that variations and modifications may be made in theparticularform of apparatus employed without departing from the spiritof our invention. Various types of operating pedal arrangements may beutilized We do not, therefore, wish to be limited to the specific formherein shown and described but claim as our invention all embodimentsthereof coming within the scope of the appended claims.

We claim:

1. In control apparatus for an automotive vehicle having a clutch, abrake and a throttle, a lever adapted to be operated by the vehicledrivers foot to control the throttle and clutch, a second lever abovesaid first named lever and having a portion adapted to be engaged by thetop of the drivers foot, said second lever being adapted to control thevehicle brake.

2. In combination in an automotive vehicle having a fluidpressureactuated clutch and brake,

a control valve for controlling the operation of said clutch and brake,said valve including a tubular housing closed at one end and having aplurality of ports extending through its wall, a piston type closuremember slidably disposed in said housing and having a plurality ofclosure portions adapted to control the flow of actuating fluid throughsaid ports in said housing, said closure portions and said ports beingso spaced and positioned that said clutch will be disengaged before saidbrake is applied, and a fluid passage extending from the closed end ofsaid housing above the end of the piston closure member to one of saidports whereby the fluid pressure conditions at said port will bemaintained in the closed end of said housing.

3. In a control system of the type described, fluid pressure actuatedclutch operating means, fluid pressure actuated brake actuating means, avalve for controlling said fluid pressure actuated means, fluid pressureconducting connections between'said valve and said means, said valve andthe atmosphere and said valve and a source of reduced pressure, saidvalve including a piston closure member movable -in a tubular housingclosed at one end and open to the atmosphere at a valve for controllingsaid fluid pressure actuated means, fluid pressure conductingconnections between said valve and said means, said valve and theatmosphere and said valve and a source of reduced pressure, said valveincluding a piston closure member movable in a tubular housing closed atone end and open to the atmosphere at its opposite end, said closuremember being adapted to control the fluid connections to both the brakeandclutch actuating means, a fluid passage from said closed end of saidhousing to the fluid pressure connections between said valve and saidbrake actuating means whereby the pressure conditions established in thebrake actuating means are also maintained at one end of said pistonclosure member, and an operating spring adapted to exert a forceopposing the action of the brake operating pressure on the closuremember and means for varying the force so applied by said spring wherebythebraking .efiort may be varied.

5. In apparatus of, the type described, a combination control valvecomprising a tubular housing having a plurality of ports and a pistonclosure member operable therein, said closure member being adapted tocontrol the flow of fluid through the ports to effect fluid pressureconnection to a brake operating device and aclutch operating device,said valve including a spring adapted to transmit a moving force to theclosure member andmeans for applying the brake device fluid pressure tooppose said spring, the clutch device fluid pressure ports being sodisposed relative to said closure member that the fluid connections tothe clutch device are not changed by the action of the brake pressure onthe closure member.

6. In a. control system of the type described,

fluid pressure actuated clutch operating means, independent fluidpressure actuated brake actuating means, a valve for controlling saidfluid pressure actuated means, fluid pressure conducting connectionsbetween said valve and said means, said valve and the atmosphere andsaid valve and a source of reduced pressure, said valve including apiston closure member movable in a tubular housing closed at one end andopen'to .the atmosphere at'its opposite end, said closure member beingadapted to control the fluid connections to both the brake and clutchactuating means.

7. In apparatus of'the type described, a conibination control valvecomprising a tubular housing having a plurality of ports and a pistonclosure member operable therein, said tubular housing havingcircumferentially extending grooves at each of said ports, saidclosuremember being adapted to control the flow of fluid through the ports toefiect fluid pressure connection to a brake operating device and aclutch operating device, said valve including a spring adapted totransmit a moving :lForce to the closure member and means forv applyingthe brake device fluid pressure to oppose said spring, the clutch devicefluid pressure ports being so disposed relative to said closure memberthat thefluid connections to the clutch device are not changed by theaction of the brake pressure on the closure member.

8. In a control system of the type described, fluid pressure actuatedclutch. operating means, independent fluid pressure actuated brakeactuating means, a valve for controlling said fluid pressure actuatedmeans, fluid pressure conducting connections between said valve and saidmeans, said valve and the atmosphere and said valve and a source ofreduced pressure, said valve including a piston closure member movablein a tubular housing closed at one end and open tothe atmosphere at itsopposite end, said tubular housing having a plurality of ports in itswall and hava ing circumferential grooves formed on the inner surface ofits wall adjacent each of said port s, said closure member being adaptedto control the fluid connections to both the brake and' clutch actuatingmeans.

9. In combination in an automotive vehicle having a fluid pressureactuated clutch and brake, a control valve for controlling the operationof said clutch and brake, said valve including a tubular housing closedat one end and having a plurality of ports extending through its wall, a

piston type closurememberslidsliydisposedin said housing snd having 1plurality ot closune portlons adapted to control the flow oi actuatingfluid through said ports in said housins. th innersurfaceotthewsllotssidhousinzbeln: circumi'erentislly grooved st-ssid ports.said closure portions and said portsbeinz so sud positioned thst llldclutch will be discussed

